@article{10_4153_CJM_2007_006_4,
     author = {Lamzouri, Youness},
     title = {Smooth {Values} of the {Iterates} of the {Euler} {Phi-Function}},
     journal = {Canadian journal of mathematics},
     pages = {127--147},
     year = {2007},
     volume = {59},
     number = {1},
     doi = {10.4153/CJM-2007-006-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2007-006-4/}
}